r4f2426 Renesas Electronics Corporation., r4f2426 Datasheet - Page 264

• Manufacturer Part Number: r4f2426
• Description: 16-bit Single-chip Microcomputer H8s Family / H8s/2400 Series
• Manufacturer: Renesas Electronics Corporation.

Section 6 Bus Controller (BSC)
A setting can be made in bits RCW1 and RCW0 in REFCR to delay RAS signal output by one to
three cycles. Use bits RLW1 and RLW0 in REFCR to adjust the width of the RAS signal. The
settings of bits RCW1, RCW0, RLW1, and RLW0 are valid only in refresh operations.
Figure 6.49 shows the timing when bits RCW1 and RCW0 are set.
Rev. 1.00 Sep. 19, 2008 Page 236 of 1270
REJ09B0466-0100
CSn (RASn)
φ
UCAS, CAS
T
Rp
(RCW1 = 0, RCW0 = 1, RLW1 = 0, RLW0 = 0)
Figure 6.49 CBR Refresh Timing
T
Rrw
T
Rr
T
Rc1
T
Rc2